Hi all, hoping that someone here might have some ideas behind this! Truck is a 93 5.0 4WD, 84k.

I've got an intermittent grinding/knocking noise from the front that I'm fairly sure is something to do with the 4wd system - it's the same noise and 'feel' as when it isn't properly engaged. I would describe it as sounding and feeling like it is semi-engaging 4wd whilst it's in 2wd, if that makes any sense!

There doesn't seem to be any particular rhyme or reason as to what will cause it, I've had it go from normal to grinding on smooth roads, after a bump in the road. Speeds at a very rough guess between 10 and 30 mph. Seems to knock more after turning left but again, sometimes will be fine. Shifting it from 2H to 4H and back usually solves it.

I'm a bit frustrated as the shop put a new (used) transfer box on it but it doesn't seem to have made any difference. I can't find any posts on the internet describing the problem for this particular generation F150 and at the moment am not in a position to keep throwing money at it, but I need it back on the road! (I'm currently relegated to a purple PT Cruiser so that's another incentive in itself ).

If anybody has any ideas or suggestions, they are all much appreciated. Thank you

 

Click this & read the caption:


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But that exact condition can't appear at this age - it's strictly a new-vehicle problem. If yours is doing that, it's because of poor maintenance &/or negligence. Have you followed the maintenance schedule using only top-quality parts & proper procedures?


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Is your truck even built the way that TSB describes? Fill in your signature:


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This caption describes the maintenance for that style of hub lock:


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